Evolutionary footprint of epistasis
Fig 2
A pair of interacting sites in a long genome.
(left) Open and filled circles: wild type 0 and mutated allele 1. Red line: existing interaction. Black line: potential interactions between sites. Dashed line: negligible interaction. Grey box: the rest of genome. (B-E) Derivation of the universal footprint of epistasis explained in the text. W is total fitness, S(W-Wpair) is entropy of the rest of genome, and fii are the haplotype frequencies. Parameter E represents the relative strength of epistasis (Eq 1).